This disclosure generally relates to an energy absorbing assembly and more particularly, to a reversibly expandable energy absorbing assembly for impact management utilizing actively controlled and engineered materials such as magnetorheological fluids and elastomers as well as electrorheological fluids and elastomers.
It is known in the prior art to provide various types of personal protection by the use of energy-absorbing devices, such as in helmets, vehicles, and the like. These products are generally designed to absorb a significant percentage of the energy from an impact. Within the vehicle, for example, various types of occupant protection devices may be employed for impact with structural body components such as door pillars, frames, headrails and the like. These components are typically made of steel tubing or steel channels that are welded together to form the structural cage or unitized body for the vehicle and may themselves absorb energy as the result of an impact. In addition, energy absorbers may also be placed over the door pillars, frames, headrails, and other parts of the vehicle to further protect the vehicle occupants during an impact event. Prior art approaches generally have used irreversibly crushable materials, such as metal, plastics or foams, irreversible air inflation devices, e.g. air bags and inflatable side curtains, rigid translation devices, e.g., extendable/retractable knee bolsters, and devices that can change the stroking forces, e.g., magnetorheological material based dampers.